Flash fire and chemical resistant fabric and garments

ABSTRACT

A flash fire and chemical barrier composite fabric, comprising a flame resistant fibrous basic layer; a radiant heat and chemical permeation barrier, the barrier including a metalized polymeric chemical permeation resistant layer film; and a clear heat sealable outer film layer overlying the radiant barrier and forming a heat sealable outer surface of the composite fabric.

PRIORITY INFORMATION

This application claims benefit to U.S. Patent Application No.61/135,457, filed Jul. 21, 2008, the contents of which are incorporatedherein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to chemical protective clothing and thefabrics used therein. More specifically the present invention relates tochemical protective composite fabrics that also have flash fireresistance.

BACKGROUND OF THE INVENTION

Over the last few decades the choices of chemical protective clothingand ensembles available to hazardous materials clean up responders andplant workers have expanded significantly. As awareness of the hazardsassociated with dangerous and toxic chemicals in the liquid and or vaporforms increased, the chemical protective fabrics began to transitionfrom rubber or PVC based fabrics to the more chemical permeationresistant film based fabrics.

ASTM International (ASTM), originally known as the American Society forTesting and Materials, is an international standards organization thatdevelops and publishes voluntary consensus technical standards for awide range of materials, products, systems, and services. In 1977 theASTM formed the F23 committee on protective clothing. This committee hasissued numerous test standards that have impacted the development ofchemical protective clothing. One such standard was ASTM F739 whichstandardized how chemical permeation through protective fabrics ismeasured. This standard, which measures chemical migration through thefabric on a molecular level, highlighted the differences betweentraditional rubber products and newer barrier films. Another standard,ASTM F1001 established a chemical test battery consisting of 15 liquidchemicals and 6 gases representing a broad base of chemical families. Ifone chooses to document to this standard, all chemicals must be testedand reported. This again highlighted the advantage of high barrier filmsover the then traditional elastomeric fabrics.

One of the earliest film based fabrics to be developed was Saranex 23laminated to Tyvek. This thin material offered considerable chemicalprotection compared to elastomeric products and solved the difficultproblem of garment decontamination since this product was designed to bedisposed of after use. U.S. Pat. No. 4,833.010 issued in 1989 describesa material that is heat sealable and exhibited greater than 8 hourspermeation resistance to all of the ASTM F1001 chemicals. This materialwas used to fabricate gas tight suits offering the highest level ofprotection while still being designed for disposal after exposure tochemicals.

In 1986 the National Fire Protection Association (NFPA) established thesubcommittee on Hazardous Materials Protective Clothing and Equipment.The first standard issued by this subcommittee was NFPA 1991 issued in1990. This standard specified performance requirements for a gas tightlevel A suit that included chemical, physical, and flammabilityrequirements. The film based products up until then offered excellentresistance to chemicals but readily burned and or melted when exposed toflame. To overcome this obstacle, the standard allowed for the wearingof a secondary outer cover typically made from a reflective metalizedflame retardant (FR) fabric. The single skin standalone suits to meetthe requirements of NFPA 1991 were typically made of composites offluoropolymers that were expensive and difficult to manufacture.Additionally, these garments offer limited radiant heat resistance asthey do not have a reflective surface.

Several attempts have been made at producing a single skin standalonematerial that offers both chemical and flash fire resistance. U.S. Pat.No. 4,792,480 describes a fabric that contains a reflective layer, achemical layer, and a fabric substrate. The reflective outer surface iscovered with a heat sealable layer of flame retardant film that isradiant heat transparent and light transparent thermoplastic film Thereis an inherent problem with making a clear transparent thermoplasticfilm flame retardant. When flame retardant additives are introduced intothe film, the result is marginal FR performance and the film becomesmilky or cloudy significantly reducing the ability of the reflectivesurface beneath it to reflect the radiant heat load. If a non flameretardant clear heat sealable film is used, it will burn off of thesurface of the composite when subjected to a vertical flame. There hasbeen no known product in the market based on the '480 patent.

U.S. Pat. No. 5,948,708 describes a fabric containing a reflective outersurface, a flame retardant fiber substrate, and a series of coextrudedcomposite polymer barrier layers on the inner surface next to thewearer's skin. While this fabric provides flame and chemical protection,it is only heat sealable on the inside surface. This means that theseams of a garment made from this composite can only be heat sealed onthe inside of the garment next to the skin. Typically the outer seams onthe reflective surface are covered with a clear FEP pressure sensitivetape. The clear FEP pressure sensitive tape can be easily removed orabraded from the metalized outer surface of the garment through usage.While the wearer may be protected by the inner seams, undesirablecontamination of the fabric substrate could occur through compromisedouter seams.

US Publication US2004/0063371A1 describes a spun-laced flame retardantnonwoven fabric laminated to a halogenated flame resistant polymericfilm This laminate offers limited chemical resistance and little or noradiant heat resistance.

US Publication US2005/0255771A1 describes a chemical and flash fireprotective fabric comprising a flame retardant fabric inner surface, achemical barrier layer, and a flame retardant outer polymer layer. Theseams formed by the outer flame retardant outer layer are heat sealable.The disadvantage of this fabric is that it does not contain a reflectivelayer to block the radiant heat load.

SUMMARY OF THE INVENTION

An object of this invention is to provide a single fabric material thatwill provide chemical protection and flash fire protection for use inconstructing garments to protect hazardous materials response personneland chemical plant workers.

It is a further object to provide radiant heat protection through theutilization of a reflective chemical barrier layer.

Yet another object of this invention is to provide for a heat sealablesurface layer over the reflective chemical barrier.

One embodiment of the present invention is a fabric comprised of amultilayer composite consisting of a flame retardant fabric, a chemicalbarrier layer with a reflective surface, and a clear thermoplastic outerlayer that is heat sealable by the application of heat and pressure orthrough the use of thermoplastic strips of seam sealing tapes.

The fabric preferably passes flammability when tested per ASTM F1358and/or ASTM D6413.

In other embodiments, the fabric creates a flash fire barrier whereinsaid flash fire is in the ambient atmosphere exposes the radiant barriermeans and the fabric providing an interior surface temperature of lessthan about 275 degrees Fahrenheit.

Another embodiment of the use of a clear non flame resistant heatsealable thermoplastic layer of the present invention over a reflectivebarrier layer. Without being bound by theory or mechanism, this is madepossible by the use of a thermal expanding adhesive layer dispersedbetween the flame retardant fiber and a metalized chemical barrierlayer. This thermal expanding adhesive layer prevents ignition of theouter clear thermoplastic layer when exposed to flash fire. In oneembodiment, the sealable outermost surface of the outer film layer canbe a clear polyurethane film laminated to the metalized barrier filmwith a tie layer selected from a group consisting of EVA, EMA, and EAA.

Another embodiment of the present invention is a fabric useful forproducing garments and ensembles that provide chemical protection, flashfire protection, and a reduction in radiant heat load that can bereadily fabricated into various configurations with heat sealable outerseams.

Another embodiment of the present invention is a flash fire and chemicalbarrier composite fabric that has a flame resistant fibrous basic layer;a radiant heat and chemical permeation barrier, the barrier including ametalized chemical permeation resistant polymeric film; and a clear heatsealable outer film layer overlying the radiant barrier and forming aheat sealable outer surface of the composite fabric.

As examples the flame resistant fibers are chosen fiberglass, carbonizedfibers, rayon, cotton, wool and aramid fibers, aromatic polyamide,polyester, or blends thereof. The chemical permeation barrier layerincludes at least one component chosen from polyvinylidene chloride,ethylenevinyl acetate, chlorinated polyethylene, polyethylene, lowdensity polyethylene, linear low density polyethylene, high densitypolyethylene, nylon, polyvinyl alcohol, polyester,polytetrafluoroethylene, fluorinated ethylene propylene, propylene,polyvinyl chloride copolymer, acrylic, acrylonitrile, and ethylene vinylalcohol. Additionally, the radiant heat and chemical permeation barriercan include a co-extruded polymeric chemical permeation resistant filmto form a multilayer barrier. The metalized layer may be adhered to thetop and/or bottom of the barrier. As an example, the radiant heat andchemical permeation barrier is a metalized polyester film Also themetalized polyester film may be between about 10 and 100 gauge inthickness.

Embodiments of the combined radiant heat and chemical barrier block 14of the 15 liquid chemicals specified in ASTM F1001 for a period of 8hours when tested per ASTM F739.

In a preferred embodiment, the combined radiant energy barrier andchemical resistant barrier is laminated to the flame retardant fabric bymeans of a flame resistant adhesive. As examples, the adhesive maycomprise a hot melt polymer or thermal set polymer. Additionally, theflame resistant adhesive preferably contains expanding graphite.

Of course, other embodiments include protective garments made from thefabric of the present invention. The protective garments are preferablyflash fire and chemical protective garments.

The garments may be sealed by hot air welded the exterior seams with aheat sealable chemical resistant tape. The garments preferably are vaportight. That is, they preferably pass the ASTM F1052 vapor tightintegrity test.

Other embodiments, aspects, and uses of the present invention, such asprotective pallet or equipment covers, for example, would be evident toone of ordinary skill in the art when reviewing this disclosure.

BRIEF DESCRIPTION OF THE DRAWING

The drawing is a cross sectional view of an example of the presentinvention. The drawing shows a five-layer laminate material of thepresent invention.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Referring to the drawing for a clearer understanding of the invention,it may be seen that five functional layers are bonded together to formthe fabric. Of course, in other embodiments of the present invention,fewer or additional layers may be used.

The layer 10 closest to the skin (base layer) is a flame resistantmaterial such as woven, nonwoven or knitted fabric formed of flameretardant fibers. This layer prevents flame impingement and forms theinterior layer closest to the skin. Examples of suitable flame retardantfibers include flame retardant-treated cotton, flame retardant-treatedrayon, and flame retardant-treated wool. Alternatively fabrics can beproduced from inherently flame retardant fibers, non-limiting examplesof which include fiberglass, carbon or carbonized fibers, aromaticpolyamide fibers, such as Nomex® and Kevlar® from DuPont, flameresistant melamine fibers such as Basofil® from Basofil Fibers LLC, andpolybenzimidazole fibers. Any combinations fibers are contemplated aswell.

As used herein, “flame resistant” is defined in NFPA 2112 “Standard onFlame-Resistant Garments for Protection of Industrial Personnel AgainstFlash Fire” as “the property of a material whereby combustion isprevented, terminated, or inhibited following the application of aflaming or nonflaming source of ignition, with or without subsequentremoval of the ignition source”. Typically, flame resistance for thepurpose of our application is measured by the criteria of ASTM F 1378and ASTM D 6413.

As an example, the fibers disclosed in United States Application Number2004/0063371, incorporated herein by reference, may be used in the baselayer. Thus, an example of the base layer is nonwoven fabric. Examplesof nonwoven fabrics include spunbond fabrics, resin bonded fabrics,thermal bonded fabrics, air-laid pulp fabrics, and stitchbonded fabrics.Additionally, the nonwoven fabric may be a spunlace fabric made from acombination of cellulosic and manmade fibers. Cellulosic fibers that maybe used to form the spunlace fabric include woodpulp fibers, cottonfibers, regenerated cellulose fibers such as Rayon® (obtained fromDuPont) or Lyocell® (obtained from DuPont), cellulose acetate fibers,cellulose triacetate fibers, jute, hemp and any bast, leaf, or stemfibers.

Manmade fibers that may be used to form the spunlace fabric includepolyester, nylon, or acrylic fibers. When combining the manmade fibersand cellulosic fibers to form the spunlace fabric, it is convenient forthe cellulosic and manmade fibers to be in the form of flat layers.Preferably, the celluosic fibers are in the form of sheets of paper andthe manmade fibers are in the form of an air-laid web of staple fibersor a nonwoven sheet of substantially continuous filaments. The webs orsheets may be bonded or nonbonded. In this example of fibers,preferably, the weight ratio of the cellulosic fibers to manmade fibersranges from 75:25 to 25:75, more preferably from 65:35 to 50:50.

Another example of fibers that can be used in the base layer are the“Fabric Layer” fibers disclosed in US Patent Application Number2005.0255771, incorporated herein by reference.

Optionally, a fire retardant additive is applied to the base layer orthe materials that comprise the base layer. Any well-known inorganicfire retardant additives can be used, including ammonium polyphosphates,ammonium dihydrogen phosphate, antimony trioxide, sodium antimonate,zinc borate, zirconium oxides, diammonium phosphate, sulfamic acid,salts of sulfamic acid, boric acid, salts of boric acid, and hydratedalumina.

Exemplary organic fire retardant additives that may be used include ureapolyammonium phosphate, chlorinated paraffins, tetrabromobisphenol-A andoligomers thereof, decabromodiphenyl oxide, hexabromodiphenyl oxide,pentabromodiphenyl oxide, pentabromotoluene, pentabromoethylbenzene,hexabromobenzene, pentabromophenol, tribromophenol derivatives,perchloropentanecyclodecane, hexabromocyclodecone,tris(2,3-dibromopropyl1)isocyanurate, tetrabromobisphenol-S andderivatives thereof, 1,2-bis(2,3,4,5,6-pentabromophenoxy)ethane,1,2-bis-(2,4,6-tribromophenoxy)ethane, brominated styrene oligomers,2,2-bis-(4 (2,3-dibromopropyl)3,5-dibromophenoxy)propane,tetrachlorophthalic anhydride, and tetrabromophthalic anhydride.

Further, any combination of fire retardant additives, whether inorganicor organic, may be used. A preferred fire retardant additive is aphosphate, such as Spartan 880® sold by Spartan Flame Retardants. Thefire retardant additive may be applied by any conventional method.

Layer 11 is a flame resistant adhesive layer. The adhesive layerincludes a thermally stable or hot melt adhesive matrix layer and mayalso optionally include a particulate material which will expand inresponse to exposure to elevated temperature. The resultingnoncombustible expanded char resists ignition and provides thermalinsulating protection to the underlying substrate. The adhesive layer ofthe present invention may be at least one of flame retardant andintumescent in nature. An intumescent adhesive coating is one thatbubbles and foams at high temperatures to form an insulating layer.Exemplary intumescent materials include, but are not limited to,melamine, pentaerythritol, fluorocarbon, graphite, bentonite, clay,phosphated or borated melamine, ammonium polyphosphate polyols and thelike.

One useful laminating adhesive is available from Dooley Chemical Inc. inChattanooga, Tenn. designated as product code DC TEX KSL. It has beenfound that this adhesive prevents ignition of both layers 12 and 13 whenthe composite is exposed to a vertical flame test.

Another example of a flame resistant adhesive layer of the presentinvention is the U.S. Pat. No. 4,058,643, which discloses adhesiveswhich are flame retardant and intumescent in nature. Thus, an adhesivelayer of the present invention such coatings contain at least four basiccompounds including: an acid source, preferably phosphoric, acarbonaceous residue source, a blowing agent, a solvent. In someinstances with respect to this example, it may be desirable to addadditional compounds to the coating including resin binders which serveto improve the flexibility of the coating after it has been applied tothe substrate film

With respect to this example, in order for intumescence to occur uponexposure to high temperatures such as those generated by an ordinaryflame, several distinct reactions take place in sequence. First, an acidsalt, such as ammonium phosphate, decomposes to yield phosphoric acidwhich reacts with a highly carbonaceous polyol, including starch orerythritol, to form a clear melt which later becomes a char.Simultaneously, gases, such as ammonia, carbon dioxide, water vapor andhydrogen chloride, are evolved from blowing agents, such as melamine andchlorinated paraffin, which gives off bubbles as the liquid mass darkensand gelation occurs forming a multicellular structure. A binder, such aspolyvinyl acetate or vinyl toluene-butadiene copolymer, may be employedto hold the intumescent fillers, and the solvent is added to control theviscosity. Organic or aqueous solvents may be employed. The acid sourcemay be obtained from a plurality of materials including monoammoniumphosphate, diammonium phosphate, ammonium polyphosphate, malaminephosphate, guanylurea phosphate, urea phosphate, ammonium sulfate andammonium borate. The ammonium phosphates have been found particularlyeffective acid source materials for purposes of the present coatingcompositions.

The carbonaceous residue source materials employed in the presentadhesive coating may include material such as sugars, e.g., glucose andmaltose, polyhydric alcohols including erythritol, pentaerythritol,sorbitol and the like, and starches. In accordance with one specificembodiment of the present invention, it has been found that, in additionto the foregoing carbonaceous residue source materials, shellac providesan excellent foamed char residue when it is employed in the fireretardant adhesive coating compositions of the present invention.Shellac has been found to be a preferred carbonaceous residue sourcematerial in view of the many advantages it offers in the adhesivecomposition portion of the laminar structures of the present invention.Shellac exhibits an ability to maintain its adhesive properties withvery high loadings of other additive compounds which may be present inthe adhesive coating composition. Shellac does not drip or migrate fromthe flame source and, thereby, eliminates undesirable wicking of theplastic material, such as polyethylene, into the insulation battingleaving the flame retardant additives in the coating behind. Further, ithas been found that shellac-based adhesives do not degrade or lose theirholding power over extended periods of time which is an essentialfeature, for example in holding and maintaining insulation materials ina fixed location in building construction. Shellac-based adhesives arenon-toxic, non-fuming and do not produce objectionable smoke when theyare subjected to combustion temperatures. As hereinabove noted, theshellac compositions assist in the formation of hard char surface at thepoint of combustion and are easily adaptable for employment from eitheran aqueous or an organic solvent media.

Suitable blowing agents which may be incorporated into the intumescentcoating compositions include melamine, guanidine, glycerine, urea andchlorinated paraffin, the latter having been found to be especiallyeffective in the present coatings.

Expandable graphite particles are another example of an effectiveintumescent material of the present invention.

Layer 12 is a one side metalized or two side metalized film that servesthe dual function of the radiant heat barrier and chemical resistancebarrier. The film may be monolithic or coextruded to include one or morelayers selected to impart chemical barrier properties to the film. Thefilm can include polyvinylidene chloride, ethylenevinyl acetate,chlorinated polyethylene, polyethylene, low density polyethylene, linearlow density polyethylene, high density polyethylene, nylon, polyvinylalcohol, polyester, polytetrafluoroethylene, fluorinated ethylenepropylene, propylene, polyvinyl chloride copolymer, acrylic,acrylonitrile, and ethylene vinyl alcohol. In one suitable embodimentthe film may be a polyester film, such as a monoaxially or biaxiallyoriented polyethylene terephthalate (PET) film. One or both surfaces ofthe film includes a metal layer, formed for example by vacuummetallizing.

Layer 13 is a coextrusion of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The EAA component of the coextruded layer13 adheres to the metalized surface of the polyester film layer 12.Layer 14 is clear low density polyethylene (LDPE) extrusion coated layerthat serves the dual function of providing a heat sealable surface andprotection for the metalized surface of the reflective barrier 12.

By “clear” is meant that the film does not contain substantial amountsof pigments or solid materials that would cause the film to appearcloudy or opaque, or otherwise substantially decrease the reflectivityof the metal coating layer. In other words, the layer is substantiallytransparent.

Test Methods

Chemical resistance of a fabric is typically measured by ASTM F739 (TestMethod for Resistance of Protective Clothing Materials to Permeation ofLiquids or Gases Under Conditions of Continuous Contact). Comparativeradiant heat resistance was measured by an in house flash fire chamberusing propane as a fuel. A thermocouple is placed inside of a closedtube of a diameter of 8 inches and height of 22 inches formed from thetest fabric. The outside surfaces of the tube are exposed to a flashfire with a temperature of about 1200 to 1500 degrees F. that typicallyhas a duration of about 5 to 7 seconds. This flashover testing issimilar in concept to that specified in NFPA 1991 (Standard onVapor-Protective Ensembles for Hazardous Material Emergencies) and NFPA1992 (Standard on Liquid Splash-Protective Ensembles and Clothing forHazardous Material Emergencies). If the sample tube survives the flashfire the temperature inside the tube is measured. This temperatureshould approximate the temperature that would occur inside the suit ifthe wearer encounters a chemical flash fire. Vertical flammability to anexposed flame is measured per ASTM F1358 (Effects of Flame Impingementon Materials Used in Protective Clothing Not Designed Primarily forFlame Resistance). An alternate method for measuring flammability isASTM D6413 (Standard Test for Flame Resistance of Textiles (VerticalTest)).

EXAMPLES

The following represents embodiments of the present invention. As such,they are to be view as being exemplary of the present invention and arenot to be view as limiting thereof.

Example 1

In a first lamination, a 40 gauge single sided metalized PET film wasextrusion laminated to a 1.5 mil cast low density polyethylene filmusing a co-extruded tie layer of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The 55 approximate weight of the coextrudedtie layer was 18 pounds per ream. This first lamination comprises thechemical and radiant heat barrier component of the composite. The firstlamination component was subjected to permeation testing per ASTM F739.This data is presented in Table 1 and Table 2, below.

The first lamination component was then adhesively laminated to a 8.5oz/yd² flame retardant treated cotton terrycloth fabric. A 10 oz/yd²expanding graphite adhesive was used to accomplish this lamination.Physical properties are summarized in Table 4. The flash fire data inTable 3 for Example 1 indicates only a 16% rise in internal temperatureas compared to the exposed metalized surface of the '708 teaching. Itcan be seen that this increase is very modest compared to fabrics of theother teachings that have heat sealable outer surfaces. Example 1 passedflammability when tested per ASTM F1358 and D6413.

Example 2

In a first lamination, a 40 gauge single sided metalized PET film wasextrusion laminated to a 1.5 mil cast low density polyethylene filmusing a co-extruded tie layer of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The approximate weight of the coextrudedtie layer was 18 pounds per ream. This first lamination comprises thechemical and radiant heat barrier component of the composite. The firstlamination was then adhesively laminated to a 5 oz/yd² nonwoven fabricof Basofil fibers. A 10 oz/yd² expanding graphite adhesive was used toaccomplish this lamination. Physical properties are summarized in Table4.

Example 2 passed flammability when tested per ASTM F1358 and D6413.

Example 3

In a first lamination, a 40 gauge single sided metalized PET film wasextrusion laminated to a 1.5 mil cast low density polyethylene filmusing a co-extruded tie layer of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The approximate weight of the coextrudedtie layer was 18 pounds per ream. This first lamination comprises thechemical and radiant heat barrier component of the composite. The firstlamination component was then adhesively laminated to a 10 oz/yd² flameretardant treated cotton terry cloth fabric. A 13 oz/yd² expandinggraphite adhesive was used to accomplish this lamination. Physicalproperties are summarized in Table 4.

Example 3 passed flammability when tested per ASTM F1358 and D6413.

Example 4

In a first lamination, a 40 gauge single sided metalized PET film wasextrusion laminated to a 1.5 mil cast low density polyethylene filmusing a co-extruded tie layer of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The approximate weight of the coextrudedtie layer was 18 pounds per ream. This first lamination comprises thechemical and radiant heat barrier component of the composite. The firstlamination was then adhesively laminated to a 6.5 oz/yd² flame retardantcotton terry cloth. A 6 oz/yd² expanding graphite adhesive was used toaccomplish this lamination. Physical properties are summarized in Table4.

Example 4 passed flammability when tested per ASTM F1358 and D6413.

Example 5

In a first lamination, a 40 gauge single sided metalized PET film wasextrusion laminated to a 1.5 mil cast low density polyethylene filmusing a co-extruded tie layer of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The approximate weight of the coextrudedtie layer was 18 pounds per ream. This first lamination comprises thechemical and radiant heat barrier component of the composite. The firstlamination was then adhesively laminated to a 3.8 oz/yd² flame retardantcotton polyester nonwoven cloth. A 7 oz/yd² expanding graphite adhesivewas used to accomplish this lamination. Physical properties aresummarized in Table 4. Example 5 passed flammability testing per ASTMD6413 and ASTM F1358.

Example 6

In a first lamination, a 40 gauge single sided metalized PET film wasextrusion laminated to a 1.5 mil cast low density polyethylene filmusing a co-extruded tie layer of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The approximate weight of the coextrudedtie layer was 18 pounds per ream. This first lamination comprises thechemical and radiant heat barrier component of the composite. The firstlamination was then adhesively laminated to a 3.8 oz/yd² flame retardantcotton polyester nonwoven cloth. A 9.6 oz/yd² expanding graphite hotmelt adhesive was used to accomplish this lamination. Physicalproperties are summarized in Table 4. Example 6 passed flammabilitytesting per ASTM D6413 and ASTM F1358.

Example 7

In a first lamination, a 40 gauge single sided metalized PET film wasextrusion laminated to a 1.5 mil cast low density polyethylene filmusing a co-extruded tie layer of low density polyethylene (LDPE) andethylene acrylic acid (EAA). The approximate weight of the coextrudedtie layer was 18 pounds per ream. This first lamination comprises thechemical and radiant heat barrier component of the composite. The firstlamination was then adhesively laminated to a 3.8 oz/yd² flame retardantcotton polyester nonwoven cloth using a 7 oz/yd² expanding graphiteadhesive. A second chemical barrier coextruded film was laminated to theback side of the nonwoven cloth using a flame retardant hot meltadhesive. The co-extruded film was 2 mils thick and consisted of LLDPEoutermost layer and multiple inner barriers of nylon and LLDPE. Theresulting composite passed flammability testing per ASTM D6413 and ASTMF1358. Expanding graphite was not necessary in the flame retardant hotmelt used to laminate the 2 mil co-extruded barrier film in order forthe composite to pass flammability. Physical properties are summarizedin Table 4.

TABLE 1 ASTM F1001 Chemical Test Battery NORMALIZED BREAKTHROUGH TIME(MINS) per ASTM F739 CHEMICAL Acetone >480 Acetonitrile >480 CarbonDisulfide >480 Dichloromethane 4 Diethylamine >480Dimethylformamide >480 Ethyl Acetate >480 n-Hexane >480 MethylAlcohol >480 Nitrobenzene >480 Sodium Hydroxide 50% >480 SulfuricAcid >480 Tetrachloroethylene >480 Tetrahydrofuran >480 Toluene >480GASES Ammonia Gas >480 1,3 Butadiene N.T. Chlorine Gas >480 EthyleneOxide Gas >480 Hydrogen Chloride Gas N.T. Methyl Chloride Gas N.T.

TABLE 2 Additional Chemicals of Interest to Petrochemical IndustryNORMALIZED BREAKTHROUGH CHEMICAL TIME (MINS) Acrylonitrile >480Aniline >480 Benzene >480 Diesel Fuel >480 Diethylethanolamine >480Dimethylamine >480 Ethylene Glycol >480 Gasoline >480 Hydrofluoric Acid48% >480 Hydrogen Peroxide >480 Kerosene >480 O-Xylene >480 Octane >480P erchlorethylene >480 Propylene Oxide 286 Sodium Methylate inMethanol >480 Tertary Butyl >480 Titanium Tetrachloride >480

TABLE 3 Flash Fire Test Data Temperature Temperature Protective FabricF. C. Unprotected Thermocouple 1200 648 Chem. Resist. FR Fabric (′377publication) 930 499 Aramid Fiber FR Fabric 355 179 Chem. Resist. FRFabric (′577 publication) 328 164 Chem. Resist. FR Fabric (′708 patent)179 82 Example 1 209 99

TABLE 4 Trapezoid Tear ASTM D752 Trapezoid Tear Machine Direction (MD)Cross Direction (XD) Example 1 15.2 lbs.  9.8 lbs. Example 2  8.3 lbs. 10.2 lbs. Example 3 15.4 lbs.  8.8 lbs. Example 4 9.81 lbs. 15.17 lbs.Example 5 6.25 lbs. 10.24 lbs. Example 6 7.19 lbs. 11.35 lbs. Example 75.96 lbs. 10.49 lbs.

Since an embodiment of the present invention contains a heat sealableouter surface, it makes it possible to construct a vapor tightprotective suit in addition to other traditional protective clothingdesigns. Vapor protective suits typically accommodate an SCBA (selfcontained breathing apparatus) and must pass the ASTM 1052 positivepressure test for vapor tight ensembles. They may also be classified asEPA Level A response suits.

As vapor protective suits are often designed for hazardous materialsresponses, it is desirable to have the broadest chemical protectionpossible since the initial response may involve an unidentified hazard.In an alternate embodiment, additional chemical protection may beachieved through the addition of one or more barrier films on theinnermost side next to the skin. This barrier may be a heat sealablemonolithic or co-extruded film. The layers may be selected frompolyvinylidene chloride, ethylenevinyl acetate, chlorinatedpolyethylene, polyethylene, low density polyethylene, linear low densitypolyethylene, high density polyethylene, nylon, polyvinyl alcohol,polyester, polytetrafluoroethylene, fluorinated ethylene propylene,propylene, polyvinyl chloride copolymer, acrylic, acrylonitrile, andethylene vinyl alcohol. A flame retardant is not necessary since thisinnermost layer is protected by the radiant reflective outer surface andthe insulative properties of the expanding adhesive and the flameretardant substrate. This innermost film may be attached to thesubstrate by thermal, extrusion, or adhesive lamination.

The invention thus being described, it will be apparent to those skilledin the art that various modifications and variations can be made in thepresent invention without departing from the scope or spirit of theinvention. Other embodiments of the invention will be apparent to thoseskilled in the art from consideration of the specification and practiceof the invention disclosed herein. It is intended that theSpecification, including the Example, be considered as exemplary only,and not intended to limit the scope and spirit of the invention.

Unless otherwise indicated, all numbers expressing quantities ofingredients, properties such as reaction conditions, and so forth usedherein are to be understood as being modified in all instances by theterm “about.” Accordingly, unless indicated to the contrary, thenumerical parameters set forth in the herein are approximations that mayvary depending upon the desired properties sought to be determined bythe present invention.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the example sections are reported as precisely aspossible. Any numerical value, however, inherently contain certainerrors necessarily resulting from the standard deviation found in theirrespective testing measurements.

Throughout this application, various publications are referenced. Allsuch publications, specifically including the ones listed below, areincorporated herein by reference in their entirety.

I claim:
 1. A flash fire and chemical barrier composite fabric,comprising: a flame resistant fibrous basic layer having a sideconfigured to face the skin of a wearer and an opposing side, the flameresistant fibrous basic layer comprising flame resistant fibers chosenfrom fiberglass, carbonized fibers, rayon, cotton, wool and aramidfibers, aromatic polyamide, polyester, or blends thereof, wherein theflame resistant fibrous basic layer is a woven, nonwoven, or knit; aradiant heat and chemical permeation barrier layer, the bonded to theopposing side of the flame resistant fibrous basic layer, the radiantheat and chemical permeation barrier including comprising a metalizedchemical permeation resistant polymeric film;, comprising one or morelayers of polyolefin, a tie layer, and a clear heat sealable outer filmbonded to the tie layer; wherein the radiant heat and chemicalpermeation barrier layer is structured such that the clear heat sealableouter film is the outermost layer providing a heat sealable outersurface thereon an intumescent material positioned between the radiantheat and chemical permeation barrier layer and the flame resistantfibrous basic layer; and a clear heat sealable outer film layeroverlying the radiant barrier layer providing a heat sealable outersurface thereon.
 2. The composite fabric of claim 1, wherein the flameresistant fibers are chosen from fiberglass, carbonized fibers, rayon,cotton, wool and aramid fibers, aromatic polyamide, polyester, or blendsthereof.
 3. The composite fabric of claim 1, wherein the radiant heatand chemical permeation barrier layer includes at least one componentchosen from polyvinylidene chloride, ethylene vinyl acetate, chlorinatedpolyethylene, polyethylene, low density polyethylene, linear low densitypolyethylene, high density polyethylene, nylon, polyvinyl alcohol,polyester, polytetrafluoroethylene, fluorinated ethylene propylene,propylene, polyvinyl chloride copolymer, acrylic, acrylonitrile, andethylene vinyl alcohol.
 4. The composite fabric of claim 3, wherein theradiant heat and chemical permeation barrier layer includes aco-extruded polymeric chemical permeation resistant film.
 5. Thecomposite fabric of claim 3, wherein the radiant heat and chemicalpermeation barrier layer is a mono-layer film with the metalized layeradhered to the top and/or bottom thereof.
 6. The composite fabric ofclaim 4, wherein the radiant heat and chemical permeation barrier layeris a co-extruded multilayer film with the metalized layer adhered to thetop and/or bottom thereof.
 7. The composite fabric of claim 1, whereinthe flame resistant fabric is a woven, nonwoven, or knit.
 8. Thecomposite fabric of claim 1, wherein the sealable outermost surface ofthe outer film layer is an extruded layer of polyolefin chosen fromLDPE, LLDPE, HDPE, EVA, EAA, and blends thereof.
 9. The composite fabricof claim 1, wherein the sealable outermost surface of the outer filmlayer is a clear polyolefin film laminated to the metalized barrier filmwith a and the tie layer is selected from a group consisting of EVA,EMA, and EAA.
 10. The composite fabric of claim 1, wherein sealableoutermost surface of the outer film layer is a clear polyurethane film.11. The composite of claim 1, further comprising a flame resistantadhesive between the radiant heat and chemical permeation barrier layerand the flame resistant fibrous basic layer, wherein the flame resistantadhesive contains the intumescent.
 12. The composite of claim 11,wherein the adhesive comprises a hot melt polymer.
 13. The composite ofclaim 11, wherein the adhesive comprises a thermal set polymer.
 14. Thecomposite fabric of claim 1, wherein the radiant heat and chemicalpermeation barrier layer blocks 14 of the 15 liquid chemicals specifiedin ASTM F1001 99a (2006) for a period of 8 hours when tested per ASTMF739 (2007).
 15. The composite fabric of claim 1, wherein the radiantheat and chemical permeation barrier layer metalized chemical permeationresistant polymeric film is a metalized polyester film.
 16. Thecomposite fabric of claim 15, wherein the metalized polyester film isbetween about 10 and 100 gauge in thickness.
 17. The composite fabric ofclaim 1, wherein the heat sealable outer layer is a polyolefin layerlaminated to the metalized barrier film with a tie layer of EAA.
 18. Thecomposite fabric of claim 1, wherein the fabric is configured to passASTM F1358 (2005) flammability test.
 19. The composite fabric of claim1, wherein the fabric passes flammability when tested per ASTM D6413(2008).
 20. The composite fabric of claim 1, wherein the compositefabric provides a flash fire barrier when exposed to a flash fire, thecomposite fabric providing an interior surface temperature of less thanabout 275 degrees Fahrenheit.
 21. A protective garment made from thefabric of claim
 1. 22. The garment of claim 21, comprising exteriorseams, wherein a heat sealable chemical resistant tape welds theexterior seams.
 23. The garment of claim 22, configured to pass the ASTMF1052 97 (2002) vapor tight integrity test.
 24. The composite of claim1, further comprising at least one additional chemical barrier layerlaminated to the skin facing side of the flame retardant fabric.
 25. Thecomposite of claim 24, wherein the additional layer is chosen frompolyvinylidene chloride, ethylene vinyl acetate, chlorinatedpolyethylene, polyethylene, low density polyethylene, linear low densitypolyethylene, high density polyethylene, nylon, polyvinyl alcohol,polyester, metalized polyester, polytetrafluoroethylene, fluorinatedethylene propylene, propylene, polyvinyl chloride copolymer, acrylic,acrylonitrile, and ethylene vinyl alcohol.
 26. The composite claim 25,wherein the additional layer is a co-extruded multi-layer.
 27. Thecomposite fabric of claim 24 1, wherein the radiant heat and chemicalpermeation barrier layer is configured to hold out at least 17 of the 21liquid and gaseous chemicals specified in ASTM F1001 99a (2006) for aperiod of 8 hours when tested per ASTM F739 (2007).
 28. A flash fire andchemical protective garment made from the fabric of claim
 24. 29. Aflash fire and chemical protective garment of claim 28, comprisingexterior seams and interior seams welded with a heat sealable chemicalresistant tape.
 30. A flash fire and chemical protective garment ofclaim 28, the garment configured to pass ASTM F1052 vapor tightintegrity test.
 31. A flash fire and chemical protective garmentcomprising a composite fabric, the composite fabric comprising: achemical barrier layer comprising co-extruded linear low densitypolyethylene layers with multiple nylon layers, the chemical barrierlayer having an outermost layer of linear low density polyethyleneconfigured for facing the wearer; a flame resistant fibrous basic layerhaving an inner surface configured for contact with a wearer bonded tothe chemical barrier layer, and an outer surface, the flame resistantfibrous basic layer comprising flame resistant fibers chosen fromfiberglass, carbonized fibers, rayon, cotton, wool and aramid fibers,aromatic polyamide, polyester, or blends thereof, wherein the flameresistant fibrous basic layer is a woven, nonwoven, or knit; a radiantheat and chemical permeation barrier, the barrier including a metalizedchemical permeation resistant polymeric film; a radiant heat andchemical permeation barrier layer bonded to the outer surface of theflame resistant fibrous basic layer, the radiant heat and chemicalpermeation barrier comprising a metalized chemical permeation resistantpolymeric film comprising one or more layers of a polyolefin, a tielayer, and a clear heat sealable outer film bonded to the tie layer;wherein the radiant heat and chemical permeation barrier layer isstructured such that the clear heat sealable outer film is the outermostlayer providing a heat sealable outer surface thereon; an adhesive layerbetween the outer surface of the flame resistant fibrous basic layer andthe radiant heat and chemical permeation barrier, the adhesive layercomprising a protective amount of intumescent sufficient to expand uponabsorbing radiant heat energy when exposed to a flash fire; and a clearheat sealable layer deposited over the outer surface of the metalizedchemical permeation resistant polymeric film; wherein the metalizedchemical permeation resistant polymeric film radiant heat and chemicalpermeation barrier layer is capable of reflecting a protective amount ofradiant heat energy passing through the clear heat sealable layer.
 32. Amethod of protecting a wearer when exposed to a chemical and a flashfire, the method comprising: providing a flash fire and chemicalprotective garment, the garment comprising: a flame resistant fibrousbasic layer having an outer surface and an inner surface configured forcontact with to face a wearer, the flame resistant fibrous basic layercomprising flame resistant fibers chosen from fiberglass, carbonizedfibers, rayon, cotton, wool and aramid fibers, aromatic polyamide,polyester, or blends thereof, wherein the flame resistant fibrous basiclayer is a woven, nonwoven, or knit; a radiant heat and chemicalpermeation barrier overlaying the outer surface of the flame resistantfibrous basic layer,a radiant heat and chemical permeation barrier layerbonded to the outer surface of the flame resistant fibrous basic layer,the radiant heat and chemical permeation barrier comprising a metalizedchemical permeation resistant polymeric film comprising one or morelayers of polyolefin, a tie layer, and a clear heat sealable outer filmbonded to the tie layer; wherein the radiant heat and chemicalpermeation barrier layer is structured such that the clear heat sealableouter film is the outermost layer providing a heat sealable outersurface thereon, the barrier including a metalized chemical permeationresistant polymeric filmradiant heat and chemical permeation configuredto reflect an amount of radiant heat energy of a flash fire; an adhesivelayer between the outer surface of the flame resistant fibrous basiclayer and the radiant heat and chemical permeation barrier the adhesivelayer comprising an intumescent; and a clear heat sealable layerdeposited over the outer surface of the metalized chemical permeationresistant polymeric film optionally, a second chemical barrier layerbonded to the inner surface of the flame resistant fibrous basic layerof the laminate, the chemical barrier layer comprising co-extrudedlinear low density polyethylene layers with multiple nylon layers, thesecond chemical barrier layer having an outmost layer of linear lowdensity polyethylene configured to face the wearer; and creating a flashfire barrier for the wearer upon exposure to a flash fire in the ambientatmosphere by at least one of: expanding the intumescent of the adhesiveafter absorbing an amount of radiant heat energy from the flash fire;and/or reflecting an amount radiant thermal heat from the flash fire offof the metalized chemical permeation resistant polymeric film.
 33. Themethod of claim 32, wherein the flash fire and chemical protectivegarment provides, during exposure to a flash fire, chemical protectionto the wearer in combination with at least two of: (i) expanding uponabsorbing a protective amount of radiant heat energy from the flashfire; (ii)(i) reducing the internal temperature rise inside the garment;(ii) charring of the expanded intumescent and thermally insulating thewearer and/or reducing ignition of the fibrous basic layer; (iv)(ii)reducing or eliminating combustion of the clear heat sealable layerdeposited over the outer surface of the metalized layer; and (v)(iii)reflecting an amount of radiant thermal heat from the flash fire. 34.The method of claim 32, wherein the intumescent is expanding graphite.35. The composite of claim 1, wherein the intumescent material isexpanding graphite.
 36. A flash fire and chemical protective garment ofclaim 31, the garment configured to pass ASTM F1052 97 (2002) vaportight integrity test.
 37. A flash fire and chemical protective garmentcomprising a composite fabric, the composite fabric comprising: a flameresistant fibrous basic layer having an inner surface bonded to theouter surface of a chemical barrier layer, the flame resistant fibrousbasic layer consisting of flame resistant fibers chosen from fiberglass,carbonized fibers, rayon, cotton, wool and aramid fibers, aromaticpolyamide, polyester, or blends thereof, wherein the flame resistantfibrous basic layer is a woven, nonwoven, or knit; a radiant heat andchemical permeation barrier layer bonded to the outer surface of theflame resistant fibrous basic layer, the radiant heat and chemicalpermeation barrier consisting of a metalized chemical permeationresistant polymeric film with one or more layers of a polyolefin, a tielayer, and a clear heat sealable outer film bonded to the tie layer;wherein the radiant heat and chemical permeation barrier layer isstructured such that the clear heat sealable outer film is the outermostlayer providing a heat sealable outer surface thereon; and optionally, asecond chemical barrier layer bonded to the inner surface of the flameresistant fibrous basic layer, the chemical barrier layer consisting ofco-extruded linear low density polyethylene layers with multiple nylonlayers, the second chemical barrier layer having an outermost layer oflinear low density polyethylene configured for facing the wearer;wherein the radiant heat and chemical permeation barrier layer iscapable of reflecting a protective amount of radiant heat energy passingthrough the clear heat sealable layer; the garment configured to passASTM F1052 97 (2002) vapor tight integrity test.